Wholesale Wastewater Meter Stations

Doppler Area Velocity Meter Station

Most open channel flow measurement methods require flow to transition from subcritical to supercritical.  In some cases, the flow transition is difficult or impossible to achieve due to conflicts with existing utilities, existing interceptor hydraulics, or downstream connections.  In those cases, alternate methods of flow measurement are needed. Perkins Engineering Consultants, Inc. (PECI), assisted a large regional service provider with an area-velocity meter to measure flow in an interceptor that was not suitable for other types of metering. Using Doppler radar and an ultrasonic level indicator, the open water surface area and the velocity of the water can be measured.  These two values are used to calculate the flow rate in the interceptor.

Parshall Flume Meter Stations

Accurate flow measurement is critical for many clients.  Used for billing, flow projection, and capacity evaluation, dedicated meter stations are used at treatment plants and in collection systems.  Designed with careful consideration of the upstream and downstream hydraulic conditions, our engineers are experienced in optimizing the entrance and exit conditions of Parshall Flumes to achieve a distinct, repeatable transition from subcritical to supercritical flow. PECI recently designed multiple wholesale meter stations for a large regional service provider.  One meter station was particularly challenging as it was experiencing hydraulic wave action that interfered with level measurement. PECI evaluated the installation and determined that the upstream interceptor could not provide the flow conditions needed for accurate measurement.  PECI recommended a vortex-type flow baffle in an upstream manhole and flattening the slope of the interceptor to improve entrance conditions.